Comment 6 for bug 1038332

I am also experiencing this problem with Ubuntu GNU/Linux v. 12.04, with Xen 4.1-amd64 (and Linux 3.2.0-23-generic)

here is the output i am seeing:
[ ##.######] powernow-k8: fid trans failed, fid 0x2, cur 0x0
[ ##.######] powernow-k8: transition frequency failed

I was able to produce this undesired result after following the procedure for installing Xen on Ubuntu's website:
https://help.ubuntu.com/community/Xen

The error appeared after executing the step:
sudo apt-get install bridge-utils
in the section Network Configuration. This is when booting into Xen, as a preceding step instructs to have Xen first in the default boot order before rebooting.